U.S. Pat. No. 4,592,269 granted to Ronald C. Lamparter Jun. 3, 1986 for a static vent device discloses a static vent assembly for a vehicle such as a school or transit bus wherein the interior of the vehicle is continuously vented to the atmosphere in such a way as to prevent the ingress of rain water into the passenger compartment.
U.S. Pat. No. 4,895,065 granted to Ronald C. Lamparter Jan. 23, 1990 for a combined static and powered vent assembly discloses a combined static and powered vent assembly for a vehicle such as a school or transit bus wherein the interior of the vehicle is continuously vented to the atmosphere in such a way that the forward movement of the bus causes an eductive drawing of air from the vehicle interior and which also includes a powered fan device for venting the vehicle interior when static or eductive venting is inadequate.
U.S. Pat. No. 4,433,506 granted to Donald L. Manning discloses a combined vent and escape hatch for a vehicle such as a school or transit bus which has a lid or cover for the vehicle roof opening. The cover has two linkages hinging opposite ends of the cover to the roof structure of the bus so that the cover can be tilted forward, tilted rearward or lifted away from the vehicle roof manually to vent the interior of the vehicle. Separable parts of one of the linkages are separated to permit the cover to be swung open fully to provide an escape hatch through the vehicle opening. Separation of the linkage parts is controlled by interior and exterior manual operators—an interior handle and an exterior knob. U.S. Pat. No. 4,964,673 granted to Ronald C. Lamparter Oct. 23, 1990 discloses another combined vent and escape hatch assembly of the same general type. The cover in the combined vent and escape hatch assemblies disclosed in these two patents is tilted or lifted away from the vehicle roof manually to vent the vehicle interior and pulled down manually to the closed position.
U.S. Pat. No. 6,572,182 granted to Ronald C. Lamparter et al. Jun. 3, 2003 discloses a vent and escape hatch assembly that is motorized, so that the cover is moved by motors to virtually any raised or tilted position or to a closed position. Separation of the linkage parts is still controlled manually to open the cover fully to provide an escape hatch.
The vent assemblies and the combined vent and escape hatches disclosed in these patents are satisfactory for their intended purpose and have been in commercial use for several years. However, further improvements are possible. For instance, the static vent assembly and the combined static and powered vent assembly disclosed in the Lamparter '269 patent and the Lamparter '065 patent both include a two-piece cover in which a smaller cover member is attached to a central region of a larger cover member. Both cover members are exposed to the environment which raises a number of concerns. First and foremost, the two-piece cover is erroneously perceived as providing a leakage path via the seam where the smaller cover member is attached to the larger cover member. The seam between the smaller cover member and the larger cover member collects dirt and is difficult to clean. Moreover, the two piece cover is not perceived as aesthetically pleasing or aerodynamically efficient.
On the other hand, the combined vent and escape hatch assemblies disclosed in the Manning '506 patent, the Lamparter '673 patent and the Lamparter et al. '182 patent do not provide any venting in the closed position nor prevent the ingress of rain water into the passenger compartment in any of its venting positions.